#!/bin/sh
# git-amb - git automake build utility
# Copyright (C) 2007 Hans Ulrich Niedermann <hun@n-dimensional.de>
#
# Build automake based git checkout in branch specific build and install trees.
# That makes it easy to compare build results from different branches.
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA


# Known to work and tested with
#  - git 1.5.3.4
# Should also work with git 1.2 and possibly older.

unset CDPATH
SED="${SED-sed}"

self=`basename "$0"`
selfdir=`dirname "$0"`
selfdir=`cd "$selfdir" && pwd`
. "$selfdir/git-ndim-sh"

SUBDIRECTORY_OK="yes"
USAGE="<command> [params...]"

LONG_USAGE="\
Build automake based git checkout in branch specific build and install trees.
For more details, see the ${self}(1) man page."
. git-sh-setup

require_work_tree

amb_detect_configure() {
    for configure_ac in \
	"${top_srcdir}/configure.ac" \
	"${top_srcdir}/configure.in"
    do
	if test -s "${configure_ac}"; then
	    break
	fi
	configure_ac=""
    done
    test -z "${configure_ac}" && die "configure.{ac,in} not found"
    configure="$top_srcdir/configure"
}

cond_cat_path() {
    path="."
    for dir
    do
	if echo "$dir" | grep '^/' > /dev/null; then
	    path="$dir"
	else
	    path="$path/$dir"
	fi
    done
    echo "$path"
}

amb_init() {
    # Equivalent bzr code:
    #   bzr log -r -1.. | sed -n 's/^branch nick: //p'
    if test "x$1" = "x"; then
	# determine currently checked out branch
	git_branch="$(git-symbolic-ref HEAD | $SED -n 's|^refs/heads/||p')"
    elif git-rev-parse --verify "$1" > /dev/null 2>&1; then
	# $1 is valid branch: use it
	git_branch="${1}"
    else
	die "Invalid branch \"$1\" given."
    fi
    test "x$(git-rev-parse --is-inside-work-tree 2> /dev/null)" = "xtrue"
    top_srcdir="$(cd_to_toplevel && pwd)"

    tmp="$(git-config amb.builddir)" || tmp="$GIT_DIR/amb/build"
    amb_builddir="$(cond_cat_path "${top_srcdir}" "$tmp")"
    top_builddir="$(cond_cat_path "${top_srcdir}" "$tmp" "${git_branch}")"

    tmp="$(git-config amb.installdir)" || tmp="$GIT_DIR/amb/install"
    amb_installdir="$(cond_cat_path "${top_srcdir}" "$tmp")"
    top_installdir="$(cond_cat_path "${top_srcdir}" "$tmp" "$git_branch")"

    amb_detect_configure
}

amb_autoreconf() {
    echo "$self: Running autoreconf for branch ${git_branch}"
    autoreconf -vis "$@" "$top_srcdir"
}

amb_cond_autoreconf() {
    if test ! -s "$configure" || test "$configure_ac" -nt "$configure"; then
	    amb_autoreconf
    fi
}

amb_configure() {
    amb_cond_autoreconf
    echo "$self: Running configure for branch ${git_branch}"
    mkdir -p "$top_builddir"
    cd "$top_builddir"
    "$top_srcdir/configure" --prefix="$top_installdir" --enable-maintainer-mode "$@"
}

amb_cond_configure() {
    test -s "$top_builddir/Makefile" || amb_configure
}

amb_make() {
    amb_cond_configure
    echo "$self: Running make for branch ${git_branch}"
    cd "$top_builddir"
    make "$@"
}

amb_printvars() {
    echo "$self: Settings for branch ${git_branch}"
    echo "$self:  source dir $top_srcdir"
    echo "$self:   build dir $top_builddir"
    echo "$self: install dir $top_installdir"
}

amb_purge() {
    echo "$self: Purging branch ${git_branch} build and install"
    echo "$self: Purging $top_builddir..."
    if test -d "$top_builddir"; then chmod -R u+w "$top_builddir"; fi
    rm -rf "$top_builddir"
    echo "$self: Purging $top_installdir..."
    rm -rf "$top_installdir"
    echo "$self: Finished."
}

amb_purge_all() {
    echo "$self: Purging ALL branches"
    echo "$self: Purging $amb_builddir..."
    if test -d "$amb_builddir"; then chmod -R u+w "$amb_builddir"; fi
    rm -rf "$amb_builddir"
    echo "$self: Purging $amb_installdir..."
    rm -rf "$amb_installdir"
    echo "$self: Finished."
}

amb_uninstall() {
    echo "$self: Uninstalling branch ${git_branch}"
    echo "$self: Purging $top_builddir..."
    rm -rf "$top_installdir"
    echo "$self: Finished."
}

amb_shell() {
    if test -d "$top_builddir"; then :; else
	die "Build directory does not exist yet: ${top_builddir}"
    fi
    echo "$self: Starting shell for branch ${git_branch}"
    export git_amb_srcdir="top_srcdir"
    export git_amb_builddir="top_builddir"
    export git_amb_installdir="top_installdir"
    amb_printvars
    export PS1="\
[Ctrl-D or 'exit' to quit $self shell for branch ${git_branch}]\n\
[<$self> \w]\n\
[<$(echo "$self" | sed 's/./-/g')> \u@\h \W]\$ \
"
    cd "$top_builddir" && ${SHELL} "$@"
}

# Abort on error
set -e

# The great command case
command="$1"
if shift; then
    case "$command" in
	builddir)
	    amb_init "$@"
	    echo "$top_builddir"
	    ;;
	installdir)
	    amb_init "$@"
	    echo "$top_installdir"
	    ;;
	autoreconf)
	    amb_init
	    amb_autoreconf "$@"
	    amb_printvars
	    ;;
	configure)
	    amb_init
	    amb_configure "$@"
	    amb_printvars
	    ;;
	make)
	    amb_init
	    amb_make "$@"
	    amb_printvars
	    ;;
	clean)
	    amb_init "$@"
	    amb_make clean
	    amb_printvars
	    ;;
	distclean)
	    amb_init "$@"
	    amb_make distclean
	    amb_printvars
	    ;;
	purge)
	    amb_init "$@"
	    amb_purge
	    ;;
	purge-all)
	    amb_init "$@"
	    amb_purge_all
	    ;;
	uninstall)
	    amb_init "$@"
	    amb_uninstall
	    ;;
	sh)
	    amb_init
	    amb_shell "$@"
	    amb_printvars
	    ;;
	*)
	    die "Invalid command line parameter: \"$command\""
	    ;;
    esac
else
    amb_init
    amb_printvars
fi

# End of file.